1. Field of the Invention
The present invention relates generally to ink cartridges comprising at least one film which covers an opening of an ink container which is configured to store ink therein, and a movable member which indicates whether an amount of ink stored in the ink cartridge is a sufficient amount of ink.
2. Description of Related Art
A known ink-jet printer is configured to dispense ink onto a sheet of paper to record an image on the sheet of paper. The known ink-jet printer has a recording head. The recording head is configured to selectively eject ink from nozzles to the sheet of paper. A known ink cartridge is configured to be removably mounted to the ink-jet printer. The ink cartridge has an ink chamber configured to store ink therein, and ink is supplied from the ink chamber to the recording head when the ink cartridge is mounted to the ink-jet printer.
The ink cartridge has a movable member disposed in the ink chamber. The movable member is configured to pivot based on the amount of ink stored in the ink chamber. When the ink is consumed and the amount of ink in the ink chamber becomes less than a sufficient amount of ink, an end of the movable member moves from a first position at which the end of the movable member is detected by a detector e.g., an optical sensor, to a second position at which the end of the movable member is not detected by the detector. Consequently, whether the ink chamber has a sufficient amount of ink stored therein may be determined based on the position of the end of the movable member.
It is desirable to reduce the size of the image recording apparatus and the thickness of the ink cartridge. Nevertheless, when the width of the ink cartridge is reduced, an arm and a floating member of the movable member may contact an inner wall of the ink cartridge, which may prevent the movable member from accurately pivoting as ink is consumed. In particular, when the pressure in the ink cartridge is reduced with respect to the atmospheric pressure, the inner wall may deform inwardly and contact the movable member even when the pressure in the ink cartridge is restored to the atmospheric pressure.